One mole of nitrogen gas at 0.8 atm takes 38 s to diffuse through a pinhole. whereas one mole of an unknown compound of xenon with flourine at 1.6 atm takes 57 s to diffuse through the same hole. Calculate the molecular formula of the compound.

When 3.06 g of solid NH₄HS is introduced into a two litre evacuated flask at 27^o C, 30% of the solid decomposes into gaseous ammonia and hydrogen sulphide. (i) K_c and K_p for the reaction at 27^o C (ii) What would happen to the equilibrium when more solid NH₄HS is introduced into the flask?

Give reasons of the following:
BeCl₂ can be easily hydrolysed.

Nitrobenzene is formed as the major product along with a minor product in the reaction of benzene with a hot mixture of nitric acid and sulphuric acid. The minor product consists of carbon : 42.86 %, hydrogen : 2.40%, nitrogen : 16.67% and oxygen : 38.07% (i) Calculate the empirical formula of the minor product. (ii) When 5.5 g of the minor product is dissolved in 45 g of benzene, the boiling point of the solution is 1.84 ^oC higher than that of pure benzene. Calculate the molar mass of the minor product and determine its molecular and structural formula. (Molal boiling point elevation constant of benzene is 2.53 K kg mol^-1)